package cn.itcast.service;

/**
 * Demo class
 *
 * @author gyc
 * @date 2021/10/19
 */

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;

@ServerEndpoint("/pay/status/{orderId}")
@Component
public class WebSocketServer {

    private final static Logger logger = LoggerFactory.getLogger(WebSocketServer.class);
    /**
     * 静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。
     */
    private static int onlineCount = 0;
    /**
     * concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
     */
    private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();

    /**
     * 与某个客户端的连接会话，需要通过它来给客户端发送数据
     */
    private Session session;

    /**
     * 接收userId
     */
    private String orderId="";
    /**
     * 连接建立成功调用的方法*/
    @OnOpen
    public void onOpen(Session session,@PathParam("orderId") String orderId) {
        this.session = session;
        webSocketSet.add(this); //加入set中
            addOnlineCount(); //在线数加1
        logger.info("有新窗口开始监听:"+orderId+",当前在线人数为" + getOnlineCount());
        this.orderId=orderId;
        try {
            sendMessage("服务器连接成功，支付成功会提示你额！");
        } catch (IOException e) {
            logger.error("webSocket IO异常");
        }
    }

    /**
    * 连接关闭调用的方法
    */
    @OnClose
    public void onClose(){
    webSocketSet.remove(this); //从set中删除
        subOnlineCount(); //在线数减1
        logger.info("有一连接关闭！当前在线人数为" + getOnlineCount());
    }

    /**
    * 收到客户端消息后调用的方法
    * @param message 客户端发送过来的消息
    */
    @OnMessage
    public void onMessage(String message, Session session){
        logger.info("收到来自窗口"+orderId+"的信息:"+message);
        //群发消息
        for (WebSocketServer item : webSocketSet) {
            try {
                item.sendMessage(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
    * @param session
    * @param error
    */
    @OnError
    public void onError(Session session, Throwable error){
        logger.error("发生错误");
        error.printStackTrace();
    }
    /**
    * 实现服务器主动推送
    */
    public void sendMessage(String message)throws IOException {
        this.session.getBasicRemote().sendText(message);
    }
    /**
    * 群发自定义消息
    * */
    public static void sendInfo(String message,@PathParam("orderId") String orderId){
        logger.info("推送消息到窗口"+orderId+"，推送内容:"+message);
        for (WebSocketServer item : webSocketSet) {
            try {
                //这里可以设定只推送给这个orderId的，为null则全部推送
                if(orderId==null) {
                    item.sendMessage(message);
                }else if(item.orderId.equals(orderId)){
                    item.sendMessage(message);
                }
            } catch (IOException e) {
                continue;
            }
        }
    }

    public static synchronized int getOnlineCount(){
        return onlineCount;
    }

    public static synchronized void addOnlineCount(){
        WebSocketServer.onlineCount++;
    }

    public static synchronized void subOnlineCount(){
        WebSocketServer.onlineCount--;
    }
}
